Rotary pumps



Jan. 16, 1962 T. J. DESKA ETAL 3,016,834

ROTARY PUMPS Filed Oct. 7, 1957 3 Sheets-Sheet 1 INVENTOR-S iF/zooaesJDES/(A Jan. 16, 1962 T. J. DESKA ETAL 3,

ROTARY PUMPS Filed Oct. 7, 1957 3 Sheets-Sheet 2 INVENTORS ii/soams J05510: BY Jo /v HAM 5y ArroR/v Y5 torque to the pump units.

3,916,834 RQTARY PUMPS) Theodore J. Deslra and John Harvey, Detroit,Mich, assigners to Eaton Manufacturing Company, illeveland, Ohio, acorporation of ilthio Filed (let. 7, 1957, Ser. No. 588,632 3 Claims.(Cl. 1tl3--4) This invention has to do with rotary pumps and provides anovel pump unit of the plural pump type.

An object of this invention is to provide a novel pump unit of theplural pump type which is of a simplified Construction and relativelymore compact than the pumps of this type heretofore available.

Another object is to provide a plural pump assembly comprising aplurality of rotary pumps in a short-coupled relation in a commonhousing with rotor means of one pump forming a side wall for pumpingchambers of an adjacent pump, such that the overall axial length of theunit is reduced to a minimum.

Still another object is to provide such a plural pump assembly in whichthe axially adjacent pumps are of the gear type with side portions ofthe rotor means of adjacent pumps in running contact and in which a gearmember of one pump has a position and size to overlie, and form the sidewall of, pumping chambers of an adjacent pump.

This invention likewise provides a plural pump assembly comprising acommon housing having two axially adjacent gear-type pumps therein oflarge and small pitch diameter respectively and in which intake and discharge ports serving the larger pump lie outside of the periphery of thecylinder of the smaller pump.

' Additionally, this invention provides a dual pump assembly having pumpcylinders extending into complemental housing sections from a commonparting plane and in which the rotor means of the pumps have theiradjacent side faces in running contact and lying substantially in theparting plane.

' Other objects and advantages of this invention will be apparent in thefollowing detailed description, and in the accompanying sheets ofdrawings forming a part of this specification and in which,

FIG. 1 is an end elevation of a plural pump assembly embodying thisinvention;

FIG. 2 is an end elevation of the plural pump assembly from the otherend thereof and with portions of the pump housing shown in section;

' FIG. 3 is a sectional view taken through the pump assembly axiallythereof and substantially as indicated by section line 3-3 of FIGS. 1, 4and 5;

FIG. 4 is a transverse section taken on section line 4-4 of FIG. 3;

FIG. 5 is another transverse section taken on section line 5-5 of FIG.3;

FIGS. 6, 7 and 8 are fragmentary sections taken respectively on sectionlines 66, 77 and 83 of FIG. 1;

FIG. 9 is a fragmentary section taken on section line 9-9 of FIG. 2;

FIG. 10 is an axial section similar to that of FIG. 3 but showing amodified construction for such a plural pump assembly; and FIG. 11 is anaxial section similar to FIG. 3 but representing another modifiedconstruction.

As one of the preferred embodiments of the present invention, FIGS. 1 to4 inclusive show a plural pump assembly 10 which comprises, in general,a common housing 11 containing axially adjacent pump units, in thisinstance two such pump units 12 and 13, and a shaft means 14 rotatablein the housing for supplying driving The pumps 12 and 13 are 3,016,834Patented Jan. 16, 1962 rotary pumps and are here shown as being of thegear type and each comprising two coaxially disposed cooperating outerand inner gear-type rotors. The pumps 12 and 13 are of two sizes; thepump 12 being the larger pump and comprising outer and inner cooperatingrotors l6 and 17, and the pump 13 being the smaller pump and comprisingouter and inner cooperating rotors 1S and 19.

The housing 11 comprises two complemental housing sections 2.0 and 21secured together as by suitable bolts 15 and having their adjacent sidefaces .22 and 23 lying in a common transverse parting plane 24. Thehousing section 2% is provided with a circular pump cylinder 25 whichextends thereinto from the side face 22 thereof and in which the rotors16 and 17 of the larger pump 12 are located. The housing section 21 isprovided with a circular pump cylinder 26 extending thereinto from theface 23 thereof and in which the rotors 18 and 19' of the smaller pump13 are located.

The housing section 20 is provided with a fiat external end face 27 andwith a circular peripheral edge 28. The housing section 21 is providedwith a central axial external boss 29, and with a radial flange 31')" ofa generally quadrangular shape and of such size that its corner portions3th: project beyond the peripheral edge 28 of the housing section 20 asshown in FIGS. 1 and 2. The projecting corner portions 30a are providedwith bolt holes 3llb. The housing section 21 also has a projecting legportion 31 formed as an extension of the boss and flange portions 29 and39.

The plural pump assembly 1% can be applied to various uses but, when thehousing 11 thereof is of the form and construction above described, theassembly can be mounted on the motor housing or engine block of aninternal combustion engine by attaching the flange 30 of the housingsection 21 to the engine block by means of studs or the like extendingthrough the bolt holes 3%. When the pump assembly 10 is mounted in thismanner, the housing section 20 projects into a bored opening of theengine block. The pumps 12 and 13 can be used for auxiliary purposes ofthe engine such as lubrication and scavenging pumps, or for any otherdesired purposes.

The outer or driven rotor 16 of the pump 12 is in the form of aninternal gear having tooth. projections or lobes 32 thereon and pocketsor tooth spaces 33 be tween the pairs of adjacent teeth. This outerrotor 16 has a circular outer periphery 34 which is rotatably slidablein the cylinder 25. The inner or driving rotor 17 is in the form of anexternal gear having teeth 35 thereon and tooth spaces 36 between thepairs of adjacent teeth.

The teeth 35 of the inner rotor 17 are fewer in number than the toothspaces 33 of the outer rotor 16, such that during rotation of the innerrotor in mesh with the outer rotor, the teeth and tooth spaces of thetwo rotors will cooperate to from pumping chambers 37 therebetween ofvariable size. The bottoms of the tooth spaces 36 of the inner rotor alllie on a common circle 38 representing the minor diameter of this rotor.The outer and inner rotors 16 and 17 are of an axial thicknesssubstantially equal to the axial depth of the cylinder 25, such thattheir side faces 39 and 4!} lie in the common parting plane 24.

The outer or driven rotor 18 of the pump 13 is in the form of aninternal gear having tooth projections or the outer rotor, such thatduring rotation of the inner rotor in mesh with the outer rotor, thecooperating teeth and tooth spaces will form pumping chambers 45therebetween of variable size.

The outer rotor 18 of the pump 13 is provided with a circular periphery46 which is rotatably slidable in the cylinder 26. The tooth spaces 42of the outer rotor 18 all have their tops lying on a common circle 47Which represents the major diameter of the pumping chambers 45 of thesmaller pump 13. The rotors 18 and 19 are of an axial thicknesssubstantially equal to the axial depth of the cylinder 26, such thattheir side faces 48 and 49 lie in the common parting plane 24.

The shaft means 14 is common to all of the pumps of the plural pumpassembly and is here shown as comprising a single shaft member 14arotatable in the housing sections 20 and 21 and extending transverselyof the pump cylinders 25 and 26. The shaft member 14:: extends throughthese pump cylinders in an eccentric relation thereto, as shown in FIGS.3, 4 and 5, and the inner rotors 17 and 19 of the pumps 12 and 13 aresecured to this shaft member as by means of the key 50, such that theinner rotors are located in a corresponding eccentric relation andmeshed engagement with respect to their associated outer rotors 16 and18.

The inner end of the shaft member 14a is rotatable in a bearing socket51 provided in the boss 29 of the housing section 21. The opposite endof the shaft member 1411 projects from the housing section 21B and isprovided with a fiat extension portion or tongue 52 to be drivinglyengaged by an available shaft or rotatable part of the engine on whichthe pump assembly 10 is mounted.

The housing section 20 is further provided with a pair ofcrescent-shaped partial intake and discharge ports 53 and 54 ondiametrically opposite sidese of the shaft member 14a and the housingsection 21 is further provided with a pair of such diametrically locatedcrescentshaped partial intake and discharge ports 55 and 56. The partialintake ports 53 and 55 lie on opposite sides of the cooperating rotorsof the pump 12 and communicate with the pumping chambers 37, as shown inFIG. 3, for supplying intake fluid thereto. The partial discharge ports54 and 56 lie on opposite sides of the cooperating rotors of the pump 12and likewise communicate with the pumping chambers 37 for receivingdelivery fluid therefrom under pressure.

For supplying intake fluid to the partial intake ports 53 and 55 of thepump 12, the housing section 21 is provided with an intake passage 58which communicates with one of the partial intake ports, in thisinstance, the partial intake port 55. The pumped fluid delivered by thepump 12 is discharged therefrom through a discharge passage 59 which isprovided in the housing section 20 and communicates 'with one of thepartial discharge ports, in this case, the partial discharge port 54.

The intake and discharge passages 58 and 59 thus provided in the housing11 for the pump 12 can be at any desired location in the housing but,when the pump 10 is I intended for mounting on an engine block in themanner explained above, the intake passage 58 is preferably formed inthe housing section 21 so as to be in the form of a groove recessed intothe face 23 and the extension leg 31 of this housing section, and thedischarge passage 59 of the housing section 20 is a substantiallyradially extending passage opening through the peripheral edge 280i thishousing section as shown in FIGS. 1, 2 and 4. With the intake anddischarge passages 58 and 59 of the pump 12 disposed in this relation,they will cooperate with suitably located corresponding fluid passagesof the engine block when the pump assembly is mounted on the latter.

The smaller pump 13 is provided with a pair of crescent-shaped intakeand discharge ports 61 and 62 which are formed in the housing section 21and located on diametrically opposite sides of the shaft member 14a.

The intake port 61 communicates with the pumping chambers 45 of the pump13 for supplying fluid thereto and the discharge port 62 communicateswith the pumping chambers 45 for receiving the pumped fluid therefromunder pressure.

For supplying intake fluid to the intake port 61 of the pump 13, thehousing section 21 is provided with an intake passage 63 communicatingwith this port and with which a supply pipe or suitable pipe fitting 64can be connected. The pumped fluid being delivered by the pump 13 isdelivered from the discharge port 62 through a delivery passage 65 ofthe housing section 21. In this instance, the delivery passage 65 isdisposed in an angular relation to the axis of the shaft member 14a andhas its outer end in communication with a delivery pocket 66 recessedinto the face 23 of this housing section as shown in FIGS. 5 and 7.

An extension delivery passages 67 is provided in the housing section 20and extends therethrough in an axial direction, as shown in FIG. 7, withone end of this extension passage in communication with the deliverypocket 66 and its other end opening through the ex ternal end face 27 ofthis housing section as a delivery port 68. When the pump unit 10 ismounted on the engine block in the relation already explained above, thedelivery port d8 will be in communication with a space or passage of theengine block. to which the pumped fluid being delivered by the pump 13is to be supplied.

By reason of the fact that the rotor means of the axially adjacent pumps12 and 13 of the pump assembly 18 have their adjacent sides lying in thecommon plane 24, as explained above, portions of the adjacent sides arein a face-to-face running contact. The rotors of the pumps 12 and 13 areof such sizes and pitch diameters that the above-mentioned circle 38representing the minor diameter for the inner rotor 17 of the largerpump 12 will always be greater than the circle 47 representing the majordiameter for the pumping chambers 45 of the smaller pump 13. It willthus be seen that the inner rotor 17 of the larger pump 12 will alwaysbe in an overlying relation to the pumping chambers 45 of the smallerpump and will form the side wall or cover for these pumping chambers. Itwill also be seen that when the rotors of the axially adjacent pumps 12and 13 are in this runnning and covering relation, no spacer orintermediate cover plate will be needed between the two pumps and therotor means of the two pumps will be in a short-coupled relation suchthat the overall axial length of the pump assembly 10 can be of aminimum dimension.

FIG. 10 of the drawings shows a plural pump assembly 79 which is similarto the pump assembly 10 above described but in which the shaft means 71comprises two shaft members 72 and 73. The shaft member 72 has the innerrotor '74 of the larger pump 75 secured thereto by means of the key 75and the shaft member 73 has the inner rotor 77 of the smaller pump 78freely rotatable thereon. In this modified form of pluralpump assembly70, the outer rotor 79 of the smaller pump 78 is connected with theinner rotor 74 of the larger pump 75 so as to be driven thereby throughthe transverse connecting pin 8th In all other respects the modifiedpump assembly 70 is similar to the above-described pump assembly 10 andfunctions in substantially the same manner with the adjacent surface ofthe rotor 74 forming a cover means for the pumping chambers 81 of thesmaller pump 78 FIG. 11 of the drawings shows another modifiedconstruction embodied in a plural pump assembly 85 wherein the shaftmeans 86 comprises a single shaft member 87 having the inner rotor 88 ofthe larger pump 39; secured thereto by means of the key 93. In thismodified pump assembly 85, the inner rotor 91 of the smaller pump 921sconnected with the inner rotor 38 of the larger pump 89 by means of thetransverse pins 93.

In all other respects the modified pump assembly 85 is similar to theabove-described pump assemblies and 70 and functions in a similar mannerwith the adjacent surface of the inner rotor 88 of the larger pump 39forming a cover means for the pumping chambers 94 of the smaller pump92.

From the accompanying drawings and the foregoing detailed description,it will now be readily understood that this invention provides a pluralpump assembly in which axially adjacent pumps located in a commonhousing have the rotor means thereof in running contact, such that aside portion of the rotor means of one pump forms a cover means forpumping chambers of the adjacent pump. It will accordingly be seen thatin a plural pump assembly, as provided by this invention, the axiallyadjacent pumps are in a close-coupled relation such that the pumpassembly will have a mini-mum axial length and will operate in asuccessful and efficient manner without need for a partition plate orintermediate cover between the axially adjacent pumps.

Although the novel plural pump assembly of this invention has beenillustrated and described herein to a somewhat detailed extent, it Willbe understood, of course, that the invention is not to be regarded asbeing limited correspondingly in scope but includes all changes andmodifications coming within the terms of the claims hereof.

Having described our invention, We claim:

1. In a dual pump assembly comprising axially adjacent pumps, a commonhousing having axially adjacent pump cylinders therein, said housingalso having a pair of intake and discharge ports therein for each ofsaid cylinders, rotor means operable in the cylinders with the axiallyadjacent side faces of the rotor means of adjacent pumps in a coplanarrunning relation, the rotor means of each pump comprising a pair ofcooperating rotatable driving and driven gear members defining variablepumping chambers in communication with the intake and discharge ports ofsuch pump, the gear member comprising the rotor means of one of saidpumps being of larger pitch diameter than the gear members comprisingthe rotor means of the other pump such that the rotor means of said onepump forms an axial side Wall of the pumping chambers formed by therotor means of said other pump, transversely extending shaft meanscomprising a drive shaft having the driving gear of only one of saidpumps secured thereto, and means connecting the driving gear of thelast-mentioned one pump to the driving gear of the other pump.

2. In a dual pump assembly comprising axially adjacent pumps, 2. commonhousing having axially adjacent pump cylinders therein, said housingalso having a pair of intake and discharge ports therein for each ofsaid cylinders, rotor means operable in the cylinders with the axiallyadjacent side faces of the rotor means of adjacent pumps in a coplanarrunning relation, the rotor means of each pump comprising a pair ofcooperating rotatable outer and inner gear-type rotors defining variablepumping chambers in communication with the intake and discharge ports ofsuch pump, the gear members comprising the rotor means of one of saidpumps bein of larger pitch diameter than the gear members comprising therotor means of the other pump such that the rotor means of said one pumpforms an axial side Wall of the pumping chambers formed by the rotormeans of said other pump, transversely extending shaft means comprisinga drive shaft having the inner rotor of one of said pumps securedthereto, and means securing the inner rotor of the other pump to theinner rotor of the last-mentioned one pump.

3. In a dual pump assembly comprising axially adjacent pumps, a commonhousing having axially adjacent pump cylinders therein, said housingalso having a pair of intake and discharge ports therein for each ofsaid cylinders, rotor means operable in the cylinders with the axiallyadjacent side faces of the rotor means of adjacent pumps in a coplanarrunning relation, the rotor means of each pump comprising a pair ofcooperating rotatable outer and inner gear-type rotors defining variablepumping chambers in communication with the intake and discharge ports ofsuch pump, the gear members comprising the rotor means of one of saidpumps being of larger pitch diameter than the gear members: comprisingthe rotor means of the other pump such that the rotor means of said onepump forms an axial side Wall of the pumping chambers formed by therotor means of said other pump, transversely extending shaft meanscomprising a drive shaft having the inner rotor of one of said pumpssecured thereto, an idler shafit rotatably supporting the inner rotor ofthe other pump, and means securing the outer rotor of the last-mentionedother pump with the inner rotor of the last-mentioned one pump.

References alited in the tile of this patent UNITED STATES PATENTS698,539 McBride Apr. 29, 1902 1,795,040 Renfrew Mar. 3, 1931 1,927,799Mann Sept. 19, 1933 2,358,275 Hess Sept. 12, 1944 2,490,115 Clarke Dec.6, 1949 2,531,808 Eames Nov. 28, 1950 2,859,698 Buehler Nov. 11, 1958FOREIGN PATENTS 819,195 Germany Oct. 31, 1951

